Short-wave radio signaling system



April 8, 1930.

R. s. OHL

SHORT WAVE RADIO SIGNALING SYSTEM Filed April 16, 1925 -6alvanometer INVENTOR l. 51 0111/ BY f ATTORNEY-1 Zermocouple Patented Apr. 8, 1930 UNITED STATES.

RUSSELL S. OHII, OF NEW YORK, N. Y., ASSIGNOR T0 AMERICAN TELEPHONE 1 AND.

TELEGRAPH COMPANY, A COBPORATIONFOF: NEW -YORK.

. SHORT-WAVE RADIO SIGNALINQSXSTEM...

Application filed April 16, 1925. Serial no. 23,639.

This invention relates to short wave radio signaling systems and particularly to means to produce an unpolarized wave of short length.

The copending application of Demarest and Ohl, Serial No. 31,434, filed May 19, 1925, discloses a parabolic reflector capable of transmitting a beam of energy, which type of reflector is particularly well adapted for signaling by short waves.

produced by the generator. The inductances The present invention is concerned with a method and means for the production of an unpolarized wave of ultra-high frequency adapted for use with a parabolic reflector of the type referred to in the said copending application, or in other ways.

This invention will be clearly understood from the following description when read in connection with the accompanying drawing, of which Figure 1 shows schematically means for the production and the radiation of an unpolarized wave of ultra-high frequency, viz, short wave length; Fig. 2 shows a variation of the radiating element in which a thermocouple and a galvanometer provide means for measuring the total antenna current, and Fig. 3 shows schematically a mode of application of the generator and the radiating element with the parabolic reflector.

In Fig. 1, the rods 1 to 6 inclusive lie in the same plane and are spaced apartby an equal angular distance. These rods are connected with the thermal element of a hot wire ammeter 7 by means of which the total antenna current may be determined. This com; b1nat1on, designated A 1n the figure, constltutes the radiating element of the system. The generating element designated B comprises a vacuum tube 8 having a plate 9, a grid 10, and a filament 11, the said plate being connected with the'grid through the inductance 12 and condenser 13. These elements'are so adjusted and proportioned as to determine the frequency of oscillations 14, 15, 16 and 17 are such as to ofler high impedance to the ultra-high frequencies and thus to prevent the dissipation of the high frequency energy through the leads connected to f= ground. The plate potential is supplied by the: source- 18 "andthe filament is energized by the source 19; Oscillations of the radiatingelement A' andin-turn this energy' wlll be impressed upon'the conductors" of the parabolic reflector repreSented by QO produced hyagenerator of the type represented by B, which maybe modulated by thetransmitter 27, will be impressed upon the rods 1- to 6 "inclusive.

transmitting and receiving apparatus should be located at a point relatively high above the earth. This is readily accomplished with the arrangement constituting my invention, as shown in Fig. 3, inasmuch as the only elements necessary within the parabolic reflector are the radiating element A and the generating element B. The batteries and modulating devices may be located upon the earth and connected with the generating device by means of specially shielded conductors which per se form no part of this inventlon.

In the operation of the system'disclosed above, oscillations set up by the generating device B will produce oscillations in the rods 1 to 6 of the radiating element A. The fields ofenergy produced by these rods as thus energized will coalesce and the result will be a field of unpolarized radio energy. When this unpolarized source is located within a parabolic reflector, such as 20, there will result an unpolarized beam of radio energy.

While this invention has been disclosed as vembodied in a particular form and arrangement of parts it is to be understood that it system comprising a plurality of rods disconv nected-from the earth and in close proximity to the said source, each rod being tuned to the-frequency of the currents from the said source, and all of the said rods lying in the same plane and being spaced apart by the same angular distance.

2. In a short wave radio signaling system, the combination with a source of ultra-high 5 frequency signaling currents of a radiating system comprising a plurality of radially projecting rods in close proximity to the said source, the said radiating system being elevated above the'earth and electrically disconnected therefrom.

3. In a short wave radio signaling system, the combination with a source of ultra-high frequency signalingcurrents, of a radiating system comprising a plurality of radially projecting rods in close proximity to the said source, and a current measuring device effectively connected with all of said rods to indicate the current in the said radiating system, which system is elevated above the earth 2{) and electrically disconnected therefrom.

In testimony whereof, I, have signed my name'to this specification this, 13th day of April, 1925.

RUSSELL S. OHL. 

